An Owl’s Digestion Process

Most owls do not bother to tear small prey such as mice and voles apart but instead swallow them whole. After eight to sixteen hours, all the nutrients available in the eaten prey have been absorbed by the bird. Owls cannot digest the fur, feathers, bones, teeth and nails of their prey, so these parts remain in the bird’s gizzard (specialized organ that grinds up food in most birds but serves as a filter for holding indigestible parts in birds of prey). This accumulation of indigestible parts takes on its pellet form (which is the shape of the gizzard) about eight hours after ingestion, but is sometimes retained by the owl for another six hours or so before being coughed up. As a rule, bones are on the inside of the pellet, and the fur and feathers form a soft coating on the outside.

The stored pellet partially blocks the entrance to the digestive system so it must be ejected before the owl can eat again. This process takes anywhere from a few seconds to several minutes. The owl appears to “yawn” several times before regurgitating the pellet. Note that the pictured Barred Owl has prey (a Deer or White-footed Mouse) in its talons, but out of necessity is getting rid of a pellet before devouring it.

WordPress.com Mary Holland posted: “Most owls do not bother to tear small prey such as mice and voles apart but instead swallow them whole. After eight to sixteen hours, all the nutrients available in the eaten prey have been absorbed by the bird. Owls cannot digest the fur, feathers, bon”

Holy ravioli! I’m so curious about how long you sat watching, before witnessing this moment that you captured for us with your camera. And in general, I’d be really interested if, sometimes, you felt like telling us some of the story that led up to a photo you share with us. Thank you, again, for offering a bit of wonder for me/us this morning!

Probably a stupid question, but, does the owl also defecate or does this process take the place of that? I’m with the other comment – I like to chew and taste my food and never let it pass my lips again!

What a great shot, Mary! On Isle au Haut, I often find pellets on the rocky shore made of broken shells, sea urchin tests, and occasionally bones. I read in Wikipedia after seeing your post that grebes, herons, cormorants, gulls, terns, kingfishers, crows, jays, dippers, shrikes, swallows, and most shorebirds cough up pellets. That’s most predatory birds. And for you squeamish folks, did you know that hares and rabbits eat their feces the first time through, and redigest them? Keeps them from being weighed down by large digestive systems. The little grassy pellets of poop you find on the lawn are the second coming of poop.

It’s called ‘cecotropes’…really not gross, rabbits are vegetarians..it’s filled with nutrients…..my rabbits (of course) did that…it’s an awesome ‘manure’ to add to any plants in your garden…especially tomatoes.

I forgot to wish you and Todd Happy Anniversary! Hope that you both enjoy the day. My house smells sooooo good from the turkey carcass simmering on the pellet stove tonight. You were right! Is this aromatherapy? I think so!

Is the photo of the owl available for purchase? I teach 4th graders about owls in 9 of our local schools. We dissect owl pellets. I would love to use this photo in my lessons since it is amazing to actually see it in action.